Compliant coupler or adaptor

ABSTRACT

A CPAP device includes a flow generator including an outlet, a humidifier including an inlet, and an adaptor connector between the outlet of the flow generator and the inlet of the humidifier. The connector includes a flexible and conformable sealing portion that is movable to accommodate misalignment.

CROSS REFERENCE TO PRIORITY APPLICATION

This application is a continuation of U.S. patent application Ser. No.15/209,207, filed Jul. 13, 2016, pending, which is a continuation ofU.S. patent application Ser. No. 13/974,277, filed Aug. 23, 2013, nowU.S. Pat. No. 9,393,377, which is a continuation of U.S. patentapplication Ser. No. 11/988,720, filed Jan. 14, 2008, now U.S. Pat. No.8,544,465, which is a U.S. national phase of International ApplicationNo. PCT/AU2006/001172, filed Aug. 15, 2006, which designated the U.S.and claims priority to U.S. Provisional Application No. 60/707,948,filed Aug. 15, 2005, the entire contents of each which are herebyincorporated by reference.

FIELD OF THE INVENTION

The present invention relates to a compliant coupling or adaptor for usein communicating pressurized breathable gas between a blower or flowgenerator and a humidifier tub for a Continuous Positive Airway Pressure(CPAP) device used to treat sleep disordered breathing (SDB) conditionssuch as Obstructive Sleep Apnea (OSA).

BACKGROUND OF THE INVENTION

Domestic treatment of OSA and other SDB is usually done using a devicethat provides CPAP, e.g., nasal CPAP. A common configuration of atreatment system comprises a CPAP device and a patient interface, e.g.,a nasal mask. The nasal mask forms a sealing interface with thepatient's nasal passages in use so that the supply of air at positivepressure from the CPAP device may be delivered to the patient's airways.In this way, while the patient is wearing a nasal mask, their mouth isuncovered.

In some situations, patients “mouth breath” during sleep. When thishappens while wearing only a nasal mask, air can pass in the mask andstraight out the patient's mouth. This can lead to drying of thepatient's airway and patient discomfort. This patient discomfort can tosome extent be alleviated by the use of a humidifier placed between theCPAP device and the patient interface.

Many humidifiers are available, although the most convenient form is onethat is either integrated with or configured to be coupled to therelevant CPAP device. While passive humidifiers can provide some relief,generally a heated humidifier is required to provide sufficient moistureto the air so that patients will be comfortable. Humidifiers typicallycomprise a water tub having a capacity of several hundred milliliters, aheating element, a control to enable the level of humidification to bevaried, an air inlet to receive air from the blower, and an air outletadapted to be connected to an air delivery conduit so that thehumidified pressurized air may be passed to the patient interface.Usually, the water tub is removable from the system so that it can berefilled when necessary.

In making a humidification tub removable, there are three problems thatneed to be overcome. First, there is a need for an air seal between theair outlet of the flow generator and the air inlet of the humidifiertub. An air seal reduces air leaks that may result in an increasedpressure drop between the air pressure generated by the flow generatorand the air pressure delivered to the patient at the patient interface.Second, for efficient humidification, there must be adequate thermalcontact between the humidification tub and the heating element. Third,it is necessary to properly align and couple the humidifier tub and theflow generator. In some cases, a system base or cradle is provided tofacilitate the correct assembly of the flow generator with thehumidifier.

SUMMARY OF THE INVENTION

One aspect of the invention relates to a coupling, adaptor and/or sealbetween the humidifier inlet and flow generator outlet.

Another aspect of the invention relates to a CPAP device including aflow generator including an outlet, a humidifier including an inlet, anda connector between the outlet of the flow generator and the inlet ofthe humidifier. The connector includes a flexible and conformablesealing portion that is movable to accommodate misalignment.

Another aspect of the invention relates to an adaptor for a CPAP device,said adaptor communicating pressurized gas between an outlet of a flowgenerator and an inlet of a humidifier, the adaptor including a mainbody having first and second ends, the first end structured to becoupled to one of the inlet and the outlet and the second end having aflexible and conformable sealing portion that is movable to accommodatemisalignment between the flow generator and the humidifier.

Other aspects, features, and advantages of this invention will becomeapparent from the following detailed description when taken inconjunction with the accompanying drawings, which are a part of thisdisclosure and which illustrate, by way of example, principles of thisinvention.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings facilitate an understanding of the variousembodiments of this invention. In such drawings:

FIG. 1 is a perspective view of a CPAP device according to an embodimentof the invention;

FIG. 1.1 is a perspective view of a humidifier tub supported by a cradleaccording to an embodiment of the present invention;

FIG. 2 illustrates a perspective view of a blower with a seal/connectoraccording to an embodiment of the present invention;

FIG. 3 illustrates the blower and seal/connector of FIG. 2 in anexploded position;

FIG. 4 is a cross section along section 4-4 of FIG. 2;

FIG. 5 is a perspective view of a humidifier and the seal shown in FIGS.2-4;

FIG. 6 is a cross sectional view of the humidifier and seal shown inFIG. 5;

FIG. 7 is a cross-sectional view illustrating a seal/connector accordingto another embodiment of the present invention;

FIGS. 7B-7C illustrate a seal/connector according to an embodiment ofthe present invention;

FIGS. 8A-8E illustrate a seal/connector according to another embodimentof the present invention;

FIGS. 9A-9E illustrate a seal/connector according to another embodimentof the present invention;

FIGS. 10A-10E illustrate a seal/connector according to anotherembodiment of the present invention;

FIGS. 11A-11E illustrate a seal/connector according to anotherembodiment of the present invention:

FIGS. 12A-12E illustrate a frame attaching portion for theseal/connector shown in FIGS. 11A-11E:

FIGS. 13A-13E illustrate a seal portion for the seal/connector shown inFIGS. 1A-11E;

FIGS. 14A-14E illustrate a seal/connector according to anotherembodiment of the present invention;

FIGS. 15A-15E illustrate a frame attaching portion for theseal/connector shown in FIGS. 14A-14E;

FIGS. 16A-16E illustrate a seal portion for the seal/connector shown inFIGS. 14A-14E;

FIGS. 17A-17E illustrate a seal/connector according to anotherembodiment of the present invention;

FIGS. 18A-18E illustrate a frame attaching portion for theseal/connector shown in FIGS. 17A-17E:

FIGS. 19A-19E illustrate a seal/connector according to anotherembodiment of the present invention; and

FIGS. 20A-20E illustrate a seal/connector according to anotherembodiment of the present invention.

DETAILED DESCRIPTION OF ILLUSTRATED EMBODIMENTS 1. CPAP Device

FIG. 1 illustrates a CPAP device 10 according to an embodiment of thepresent invention. As illustrated, the CPAP device 10 includes a flowgenerator 20 and a humidifier 30 adapted to be coupled to the flowgenerator 20. The humidifier 30 and the flow generator 20 may be mountedto or supported by a common support or cradle.

2. Humidifier

The humidifier 30 includes a humidifier tub 50 having a base plate 52sealed to the bottom of the tub 50. The humidifier 30 includes or isotherwise associated with a heating element or plate that may beprovided to a cradle 40, 540 (FIG. 1.1, FIGS. 5-6). The cradle 40, 540includes a portion for supporting the flow generator. The tub 450 inFIG. 1.1 is slightly different from tub 50 in FIG. 1, e.g., tub 450includes flattened sides 482 in addition to a base plate 452, an inlet454, and an outlet 456 to facilitate alignment with cradle 40, 540. Thetub 50 includes an inlet 54 adapted to be in fluid communication with(i.e. not necessarily directly) the outlet 24 of the flow generator 20,and an outlet 56 adapted to be connected to an air delivery conduit. Theair delivery conduit includes one end coupled to the outlet 56 of thetub 50 and an opposite end coupled to a patient interface. The patientinterface comfortably engages the patient's face and provides a seal.The patient interface may have any suitable configuration as is known inthe art, e.g., full-face mask, nasal mask, oro-nasal mask, mouth mask,nasal prongs, etc.

The tub 50 and base plate 52 define a chamber that is adapted to receivea volume of water, e.g., several hundred milliliters. The inlet 54 andthe outlet 56 are both in communication with the chamber. In use, asupply of pressurized air from the flow generator 20 enters the inlet 54of the tub 50 and collects moisture through contact with the waterwithin the tub 50 before continuing on to the outlet 56 and to thepatient via the air delivery conduit.

The humidifier tub 50 may be structured such as the humidifier describedin U.S. Patent Application No. 60/707,949, entitled “Humidifier Tub ForCPAP Device”, filed Aug. 15, 2005, the contents of which areincorporated in its entirety by reference herein. Also, the flowgenerator 20 may be structured and controlled such as the flow generatordescribed in U.S. Patent Application No. 60/707,951, entitled “Low CostCPAP Flow Generator and Humidifier Assembly”, filed Aug. 15, 2005, thecontents of which are incorporated in its entirety by reference herein.

3. Seal Between Humidifier and Flow Generator

FIGS. 2-4 illustrate a connector 60 according to an embodiment of thepresent invention. The connector 60 interconnects the outlet 24 of theflow generator 20 and the inlet 54 of the tub 50. Moreover, theconnector 60 provides a pressure-activated or ‘self-energizing’ faceseal that provides a seal between the flow generator 20 and the tub 50upon docking, coupling and/or activation of the flow generator. The sealaccommodates misalignment and manufacturing tolerances as describedbelow.

As illustrated, the connector 60 provides a channel 62 (FIG. 4) todeliver pressurized air from the flow generator 20 to the humidifier tub50. In the illustrated embodiment, the connector 60 is removablyattached to the flow generator 20 and is structured to sealingly engagewith the inlet 54 of the tub 50.

As best shown in FIG. 4, the connector 60 in this example includes twocomponents that are coupled to one another. Specifically, the connector60 includes a firm frame attaching portion 64 and a flexible sealingportion 66. The firm frame attaching portion 64 is preferablyconstructed of a plastic material and includes an attachment structurethat enables secure attachment to the outlet 24 of the flow generator20. For example, the attachment structure may be in the form of asnap-fit clip that includes one or more protrusions 68 adapted to engagewithin a corresponding groove 70 provided in the outlet 24 with a snapfit, as shown in FIG. 4. However, the attachment structure may haveother suitable configurations.

The flexible sealing portion 66 comprises a bellows-type conforming faceseal 72 preferably made from silicone or other similar material thatdoes not provide problems with creep in use. The bellows-type conformingface seal 72 comprises an aperture 74 that is adapted to abut the inlet54 of the humidifier tub 50. The flexible sealing portion 66 furtherincludes an internal sealing element 76, e.g., wiper seal, thatindependently seals to the outlet 24 of the flow generator 20 to preventair leakage through the connection between the flow generator 20 and thehumidifier tub 50. Any means of providing a seal between the flowgenerator 20 and humidifier tub 50 is encompassed within the scope ofthe invention. For example, the internal sealing element 76 may be inthe form of a compression sealing ridge or a wiper seal. The flexiblesealing portion 66 is constructed such that it preferably does not haveany split lines (from the tooling) on the outer sealing face that mayinterfere with obtaining a satisfactory pressure seal.

In addition, the flexible sealing portion 66 includes an interlockingstructure that is structured to interlockingly engage a complementaryinterlocking structure provided on the firm frame attaching portion 64.In the illustrated embodiment, the sealing portion 66 includes a groove78 that interlocks with a protrusion 80 provided on the frame attachingportion 64. This arrangement interlocks the sealing portion 66 to theframe attaching portion 64. However, the sealing portion 66 may becoupled to the frame attaching portion 64 in other suitable manners.

Alternatively, the entire connector 60 may be made of silicone or asilicone-like material with differing rigidity characteristics for thefirm frame attaching portion 64 and the flexible sealing portion 66. Forexample, as shown in FIG. 7, the connector 60 may have a one-piececonstruction and the frame attaching portion 64 may have a cylindricalstructure adapted to sealingly engage the outlet 24 of the flowgenerator 20.

Preferably, the connector 60 has a round shape to provide minimalout-of-mold distortion. The face seal 72 of the flexible sealing portion66 has approximately 2 mm to 3 mm interference from the nominal contactpoint to ensure sufficient contact when the connector 60 is pushedagainst the inlet 54 of the humidifier tub 50. The aperture 74 on thesealing face 72 may be larger than the inlet 54 of the tub 50 in orderto accommodate the various misalignment and manufacturing tolerances ofthe connector 60 to outlet 24 of the flow generator 20, to ensuresufficient passage of air flow through the connector 60.

Advantageously, the face seal 72 provides for tolerance in movement inall directions while aligning the humidifier tub 50 and the flowgenerator 20. For example, the face seal 72 is flexible axially(forwards and backwards), laterally (upwards, downwards, and/orsideways), angularly, pivotally, and/or rotationally. Preferably, theface seal is flexible in all directions, although it may be moreflexible in some but more rigid in others.

The face seal 72 may be flexible within a predetermined range. Forexample, the face seal 72 may be axially and/or laterally flexiblewithin a range of about 1-5 mm, preferably about 2-3 mm. However, theface seal 72 may be axially and/or laterally flexible less than 1 mm orgreater than 5 mm. Also, the face seal 72 may be angularly, pivotally,and/or rotationally flexible within a range of about 1-10°, preferablyabout 3-6° or about 5°. However, the face seal 72 may be angularly,pivotally, and/or rotationally flexible less than 1° or greater than10°.

In use, the firm frame attaching portion 64 of the connector 60 issecurely attached to the outlet 24 of the flow generator 20 and thebellows-type conforming face seal 72 on the flexible sealing portion 66protrudes therefrom. The air inlet 54 of the humidifier tub 50 ispositioned adjacent to or abutting the face seal 72. When pressurizedair flows out through the outlet 24 of the flow generator 20, the faceseal 72 fills with air and establishes a pressurized face seal with theinlet 54 of the humidifier tub 50.

FIGS. 7B and 7C illustrate an embodiment of the connector 60 forming aseal with the inlet 54 of a humidifier tub. As shown in FIG. 7B, theconnector 60 is positioned adjacent the inlet 54 such that thebellows-type conforming face seal 72 is spaced from the inlet 54. Aspressurized air flows out through the outlet of the flow generator (asindicated by the arrow), the face seal 72 fills with air and expandsinto engagement with the axial end or axially facing surface of theinlet 54 as shown in FIG. 7C. That is, the face seal 72 balloonsoutwardly to form a cylindrical face seal with the inlet 54.

The bellows-type conforming face seal 72 provides a flexible bellows orgusset that allows the face seal 72 to self align with the inlet 54.That is, the flexibility and freedom of movement of the face seal 72(e.g., in all directions within a predetermined range) allows the faceseal 72 to form a seal with the inlet 54 even if they are misaligned.Specifically, the face seal 72 can still form a seal with the inlet 54even if the axis of the connector 60 is not aligned with the axis of theinlet 54. This arrangement accommodates the various misalignments thatmay occur between the connector 60 and the inlet 54.

Although the connector 60 has been described as being attached to theoutlet 24 of the flow generator 20, in an alternative embodiment theconnector 60 may be attached to the inlet 54 of the humidifier tub 50and the flexible sealing portion 66 may abut the outlet 24 of the flowgenerator 20. In a further embodiment, the connector 60 may bepermanently attached to either the outlet 24 of the flow generator 20 orthe inlet 54 of the humidifier tub 50. However, the connector 60 ispreferably a separate component that can be easily replaced or removedfor cleaning or sterilization purposes.

3.1 Alternative Coupling Between Humidifier and Flow Generator

FIGS. 8A-20E illustrate additional embodiments for coupling the flowgenerator to the humidifier tub. Common reference numbers are used todenote like parts. Each adaptor 60 includes a main body having a firstend for connection to either the inlet of the humidifier tub or theoutlet of the flow generator. A second end of the main body includesflexible sealing portion 66 having a face seal 72 that in the examplesshown has one or more bellows portions or convolutions. The face seal isintended to be placed in contact with or adjacent to either thehumidifier tub or the flow generator.

FIGS. 8A-9E show two adaptor embodiments, each of which is provided withone or two (or more) protruding ridges 60.1 designed to provide an extranoise seal. In the event or two or more ridges, they are axially spacedalong the axis of the main body. As shown in FIG. 8E, the beginning ofthe bellows portion has a relatively sharp angle to provide morerigidity. Comparatively, the bellows portion in FIG. 9E is verycompliant and allows a large tolerance to movement and positioning. InFIG. 9E, the bellows portion has a gradually curved cross section. InFIG. 8E, the bellows portion has a first portion 60.2 that is graduallycurved and a second portion 60.3 that is more sharply angled relative tothe first portion.

The adaptor of FIGS. 10A-10E is similar to the adaptor in FIG. 7, and ismolded as a single piece that simply slides onto the flow generatoroutlet (or the humidifier tub inlet, depending on the arrangement). Thisdesign is very compliant and allows a large tolerance to movement andpositioning. In another variant (shown FIGS. 20A-20E), one or more(three shown) slight protrusions 60.4 can be located within the bellowsto better prevent the outer face from sucking inwards and sealing to oragainst the inside surface of the bellows due to any vacuum that may becreated once the flow generator has been activated to generatepressurized flow of gas, e.g., in the range of 4-30 cmH₂O, typically8-15 cmH₂O.

FIGS. 11A-E and FIGS. 14A-E illustrate two embodiments having two piecedesigns, each adaptor or connector including a relatively rigid frameattaching portion (shown in isolation in FIGS. 12A-E and 15A-E,respectively) to attach to the flow generator outlet (or tub inlet) anda flexible bellows portion (shown in FIGS. 13A-E and 16A-E,respectively) having a face seal to abut and seal to the tub inlet orthe flow generator outlet. The frame attaching portion provides a firmattachment to the flow generator. The connection between the bellowsportion and the frame attaching portion is similar to the embodiment ofFIG. 4, in which the sealing portion includes a groove 78 and the frameattaching portion includes a protrusion 80. Thus, the bellows/sealingportion may be replaced as required. The frame portion in FIGS. 14A-15Ehas flexible sides 60.5 that are squeezed inwards (using the fingergrips shown) to facilitate repeated attaching and detaching of theadaptor from the flow generator outlet or the tub inlet. When the sides60.5 are squeezed, the frame attaching portion takes on a more ovalshape such that locking tabs 60.6 can be released from a correspondingflange that can be provided to either the tub inlet or the flowgenerator outlet.

FIGS. 17A-18C illustrate an adaptor having a two part structure,including a sealing portion and a frame attaching portion that areconnected to one another as described above. The sealing portion 66 isshown in isolation in FIGS. 16A-16E. The frame attaching portionincludes one or more (three shown) flexible arms 60.7 each of whichincludes a locking tab 60.8.

FIGS. 19A-19E illustrate an adaptor having two bellow portions with anaxial gap 66.1 therebetween to provide a more compliant seal, while atthe same time giving a wide tolerance to movement and positioning. Thisdesign is a single piece construction that simply slides onto the flowgenerator outlet port or the tub inlet. The adaptor includes an internalsealing element 60.9.

4.0 Mechanism for Retaining Humidifier in Cradle

The CPAP device 10 may include a cradle 40, 540 (FIG. 1.1, FIGS. 5-6)structured to support the humidifier tub 50, 450 in an operativeposition with respect to the flow generator 20. The cradle 40, 540 mayinclude a heater element or plate that includes a heating element, e.g.,a ceramic heating element. The cradle also includes a movable lockingmechanism 544 as part of a humidifier receiving section 546 of thecradle 540, the movable locking mechanism being movable to insert thehumidifier tub 50, 450 into humidifier receiving section 546 beforereturning to a position which securely holds tub 50, 450 and arrangesthe tub such that the heating element and base plate 52, 452 (FIG. 1,FIG. 1.1) are in thermal contact. The locking mechanism may bespring-loaded. In use, the cradle 40, 540 receives the humidifier tub50, 450 so that the heating element is in thermal contact with the heatconducting base plate 52, 452 of the humidifier tub 50, 450. Thisarrangement allows water contained within the humidifier tub 50, 450 tobe heated to provide sufficient moisture to the air so that patientswill be comfortable.

The cradle 40, 540 may provide one or more of the following functionalfeatures for the humidifier tub 50, 450: allow the humidifier tub 50,450 to be correctly oriented with respect to the flow generator 20;securely lock the humidifier tub 50, 450 within the cradle such that itcannot be easily pulled out during use; ensure good thermal contactbetween the humidifier tub 50, 450 and the heater plate present in thecradle; allow easy docking of the humidifier tub 50, 450, especially forfrail, elderly users; and for safety reasons, limit access to hot areasof the humidifier chamber when heat is being transferred from the heaterplate to the heat conducting base plate 52, 452 of the humidifier 30,once the humidifier tub 50, 450 is docked within the cradle.

While the invention has been described in connection with what arepresently considered to be the most practical and preferred embodiments,it is to be understood that the invention is not to be limited to thedisclosed embodiments, but on the contrary, is intended to cover variousmodifications and equivalent arrangements included within the spirit andscope of the invention. Also, the various embodiments described abovemay be implemented in conjunction with other embodiments, e.g., aspectsof one embodiment may be combined with aspects of another embodiment torealize yet other embodiments. Further, each individual feature orcomponent of one embodiment alone may constitute and additionalembodiment. In addition, while the invention has particular applicationto patients who suffer from OSA, it is to be appreciated that patientswho suffer from other illnesses (e.g., congestive heart failure,diabetes, morbid obesity, stroke, barriatric surgery, etc.) can derivebenefit from the above teachings. Moreover, the above teachings haveapplicability with patients and non-patients alike in non-medicalapplications.

1-20. (canceled)
 21. A connector for a CPAP system, the CPAP systemincluding a flow generator configured to generate a flow of breathablegas to be delivered to a patient and a tub configured to contain asupply of liquid, the connector comprising: a flexible sealing portioncomprising a bellows convolution having at least one bellows protrusionlocated within the bellows convolution to support the bellowsconvolution, the bellows convolution further comprising a facing surfaceconfigured to seal against a tub surface surrounding an opening of thetub, the facing surface surrounding a bellows aperture; and a channelextending through the flexible sealing portion, and the channelconfigured to deliver the flow of breathable gas through the bellowsaperture.
 22. The connector according to claim 21, wherein the at leastone bellows protrusion includes a plurality of bellows protrusionsspaced circumferentially around the bellows convolution.
 23. Theconnector according to claim 21, wherein the flexible sealing portion isconstructed of silicone.
 24. The connector according to claim 21,wherein the bellows aperture is open when the facing surface is not incontact with the tub.
 25. The connector according to claim 21, furthercomprising an attaching portion having an attachment structure adaptedto attach to the flow generator, the attaching portion constructed of aplastic material.
 26. The connector according to claim 25, wherein thechannel extends axially through the attaching portion and the flexiblesealing portion along a straight path.
 27. The connector according toclaim 25, wherein the attachment structure comprises a snap-fit clipincluding at least one protrusion adapted to engage within a grooveprovided in an outlet of the flow generator with a snap fit.
 28. Theconnector according to claim 25, wherein the flexible sealing portionand the attaching portion have differing flexibility characteristics.29. The connector according to claim 25, wherein the channel extendsthough the attaching portion.
 30. The connector according to claim 21,wherein the bellows aperture has a diameter that, prior to engaging withtub surface, is larger than a diameter of the opening of the tub. 31.The connector according to claim 21, wherein, in use, the flexiblesealing portion is configured to be filled with air to support sealingengagement between the facing surface and the tub surface surroundingthe opening of the tub.
 32. A CPAP system comprising: a first CPAPcomponent and a second CPAP component; and a connector positionedbetween the first CPAP component and the second CPAP component, theconnector configured to provide a sealed flow path for breathablepressurized gas passing between the first CPAP component and the secondCPAP component, wherein the connector comprises a flexible bellowssealing portion, the flexible bellows sealing portion comprising abellows convolution adapted to sealingly engage a facing portionsurrounding a port in the first CPAP component, and the bellowsconvolution further comprising at least one bellows protrusion locatedwithin the bellows convolution to support the bellows convolution, andwherein the bellows convolution includes a sealing face and an apertureformed through the sealing face.
 33. The CPAP system according to claim32, wherein the flexible bellows sealing portion is constructed ofsilicone.
 34. The CPAP system according to claim 32, further comprisinga plurality of bellows protrusion spaced circumferentially around thebellows convolution.
 35. The CPAP system according to claim 32, whereinthe connector comprises an attaching portion having an attachmentstructure adapted to attach to one of the first CPAP component and thesecond CPAP component, the attaching portion constructed of a plasticmaterial.
 36. The CPAP system according to claim 35, wherein theflexible bellows sealing portion and the attaching portion havedifferent flexibility characteristics.
 37. The CPAP system according toclaim 35, wherein the flexible bellows sealing portion has an outerdiameter larger than an outer diameter of the attaching portion.
 38. TheCPAP system according to claim 35, wherein the attaching portion isadapted to attach to the second CPAP component.
 39. The CPAP systemaccording to claim 32, wherein the aperture has a diameter that, priorto engaging with the facing portion, is larger than a diameter of theport.
 40. The CPAP system according to claim 32, wherein, in use, theflexible bellows sealing portion is configured to be filled with air tosupport sealing engagement between the sealing face of the bellowsconvolution and the facing portion surrounding the port in the firstCPAP component.
 41. The CPAP system according to claim 32, wherein theaperture is open when the bellows convolution is not in contact with thefacing portion.
 42. The CPAP system according to claim 32, wherein thefirst CPAP component is a humidifier tub and the second CPAP componentis a flow generator.
 43. A CPAP device, comprising: a flow generatorconfigured to generate a flow of breathable gas to be delivered to apatient and adapted to be coupled to a humidifier tub; a connectorconfigured to engage with an opening in a facing surface of thehumidifier tub, the connector comprising a flexible bellows sealingportion, the flexible bellows sealing portion comprising a bellowsconvolution, the bellows convolution having a sealing face surrounding abellows aperture, and the bellows convolution further comprising atleast one bellows protrusion located within the bellows convolution tosupport the bellows convolution; and a channel extending through theflexible bellows sealing portion, and the channel configured to deliverthe flow of breathable gas.
 44. The CPAP device according to claim 43,wherein the flexible bellows sealing portion is constructed of silicone.45. The CPAP device according to claim 43, wherein the bellows aperturehas a diameter that, prior to engaging with the facing surface, islarger than a diameter of the opening in the facing surface of thehumidifier tub.
 46. The CPAP device according to claim 43, wherein, inuse, the flexible bellows sealing portion is configured to be filledwith air to support sealing engagement between the sealing face of thebellows convolution and the facing surface surrounding the opening inthe humidifier tub.
 47. The CPAP device according to claim 43, furthercomprising a plurality of bellows protrusion spaced circumferentiallyaround the bellows convolution.
 48. The CPAP device according to claim43, wherein the bellows aperture is open when the sealing face is not incontact with the facing surface.
 49. The CPAP device according to claim43, wherein the connector further comprises an attaching portion havingan attachment structure adapted to attach to the flow generator, theattaching portion constructed of a plastic material.
 50. The CPAP deviceaccording to claim 49, wherein the flow generator further comprises anoutlet and a groove provided at the outlet, and wherein the attachmentstructure comprises a snap-fit clip including at least one protrusionadapted to engage within the groove with a snap fit.
 51. The CPAP deviceaccording to claim 49, wherein the flexible bellows sealing portion andthe attaching portion have differing flexibility characteristics. 52.The CPAP device according to claim 49, wherein the channel extendsaxially through the attaching portion and the flexible bellows sealingportion along a straight path.
 53. The CPAP device according to claim49, wherein the channel extends though the attaching portion.